Support Style Sharing for Shadow DOM V1

third_party/WebKit/Source/core/dom/Element.cpp

Index: third_party/WebKit/Source/core/dom/Element.cpp
diff --git a/third_party/WebKit/Source/core/dom/Element.cpp b/third_party/WebKit/Source/core/dom/Element.cpp
index 7a778aa8dfc8f2c070747c7e2903ea11cfa59b25..8f1e58de7c0335054f84c4f641e02b9a70e4a78b 100644
--- a/third_party/WebKit/Source/core/dom/Element.cpp
+++ b/third_party/WebKit/Source/core/dom/Element.cpp
@@ -4023,10 +4023,6 @@ bool Element::supportsStyleSharing() const {
     return false;
   if (isHTMLElement() && toHTMLElement(this)->hasDirectionAuto())
     return false;
-  // TODO(kochi): This prevents any slotted elements from sharing styles.
-  // Investigate cases where we share styles to optimize styling performance.
-  if (isChildOfV1ShadowHost())
-    return false;
   if (hasAnimations())
     return false;
   if (Fullscreen::isFullscreenElement(*this))